BORIC acid and sodium borate are sufficiently poisonous to cause severe symptoms and death when used in amounts commonly considered to be perfectly harmless. Boric acid is readily absorbed by a number of different routes and is particularly insidious in that symptoms may be minimal until a lethal or near lethal dose has been absorbed. A number of cases of boric-acid poisoning have been reported in the literature, but relatively few are accompanied with laboratory data, autopsy findings, or tissue analyses for boron. A number of deaths, particularly in infants, are mentioned in the literature but have not been adequately reported. References to boric-acid poisoning are almost completely absent from the pediatric journals. The following case is presented because it occurred in an older infant without a severe complicating disease and because a complete autopsy, including tissue analysis for boron, was performed.